Preliminary observations of heat treatment to control Phytophthora ramorum in infected wood species: an extended abstract

Abstract

Identification of appropriate phytosanitary treatments that can be used for certifying solid wood packing material movement from areas infested or threatened by actionable plant pests and pathogens into uninfested areas is mportant. Heat treatment has been used on commodities to control fungal diseases and insect infestations for many years. The restricted use of methyl bromide has revived the interest on heat disinfestation for commodities. The purpose of this research is to determine the efficacy of heat treatment to control Phytophthora ramorum in wood species. Artificially inoculated and naturally P. ramorum-infected tanoak rounds and boards were heat-treated in a dry kiln set at the temperatures 50, 56, 60, and 65°C for 30, 45, and 60 minute durations. Core temperature, heating time, wet bulb, and dry bulb temperatures were monitored. Phytophthora. ramorum was detected in wood using baiting and plating echniques before and after the treatment. Preliminary data showed that the required phytosanitary temperature of 56°C for 30 minutes might not be adequate to kill P. ramorum in wood. However, laboratory techniques have been redefined for subsequent tests using the temperatures of 50, 56, 62, and 68°C for 15, 30, and 60 minute durations.

Parent Publication

• Proceedings of the sudden oak death third science symposium

Citation

Tubajika, K.M.; Singh, R.; Shelly J.R. 2008. Preliminary observations of heat treatment to control Phytophthora ramorum in infected wood species: an extended abstract. In: Frankel, Susan J.; Kliejunas, John T.; Palmieri, Katharine M., tech. coords. 2008. Proceedings of the sudden oak death third science symposium. Gen. Tech. Rep. PSW-GTR-214. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. pp. 477-480